Dust Cap Replacement

[Leoken]

Ok Well my sub caught a bit too much power when i first turned my stereo on and well my dust cap blew off...literally on fire. The rubber surround also ripped about a quarter of the way through but i already repaired that. Amazingly enough the speaker is fine but its supposed to be a sealed box and is now venting through the voice coil. So i was wondering what might be something inexpensive and easy to find that i could replace it with. It is the infinity qa 10 inch subwoofer. Dont think a pic is necessary.

[nunayafb]

Dont think a pic is necessary

First off dont you EVER blow something up and not show us!

Second just head down to your local speaker repair shop and pick up a cap, it might affect the cone damping slightly but if you match porosity it should not be too bad at sub frequencies. By porosity I mean some speakers use porous dust caps to help/replace a motor vent.

Third, if only half of the surround is torn this tells me that either the cone came out unevenly and tore half, or the surround had a weak spot and tore there. If the first scenario happened I doubt the speaker is fine I would bet the cone or cone/spider attach point was damaged. Even if it is not visible, if the second happened you might get lucky although you will still need to replace the surround.

Finally how was enough heat generated to ignite the cap and not melt the insulation on the vc wire, or anything else for that matter?

[Leoken]

Heh i gotcha. Ill snap a pic later i guess. The surround was only a quarter of the way torn off so i pushed the cone down gently and used a rubber cement type glue evenly attaching the surround to the cone. I figure it just became lose because of how old the speakers are. They were made in the late seventies i beleive. Now the speaker im pretty sure nothing is wrong with it. It poweres up fine the voice coil doesnt rub when pushed in. The dust cap on the other one almost feels like some kind of cardboard so what might i look for as porosity goes? And i dont know how the voice coil survived but i am impressed with infinity cuz it literally went through hell and still pumps out music like nothing ever happned. Though i ended up having to replace some of the capacitors on the crossover. They were partially fried.

Originally posted by nunayafb

First off dont you EVER blow something up and not show us!

Second just head down to your local speaker repair shop and pick up a cap, it might affect the cone damping slightly but if you match porosity it should not be too bad at sub frequencies. By porosity I mean some speakers use porous dust caps to help/replace a motor vent.

Third, if only half of the surround is torn this tells me that either the cone came out unevenly and tore half, or the surround had a weak spot and tore there. If the first scenario happened I doubt the speaker is fine I would bet the cone or cone/spider attach point was damaged. Even if it is not visible, if the second happened you might get lucky although you will still need to replace the surround.

Finally how was enough heat generated to ignite the cap and not melt the insulation on the vc wire, or anything else for that matter?

[nunayafb]

The dust cap on the other one almost feels like some kind of cardboard so what might i look for as porosity goes?

If still recognizable bring it or the other speaker if you have more than one down to the repair shop so the tech can match it.
If you dont live near any shops then you'll have make contact with an out of town shop and see if you can ship the burnt one to them for matching, it may end up being cheaper just ordering a couple different styles from partsexpress and hoping one works. You might consider replacing both dust caps in order to keep them identical.

Good luck!

[ocool_15]

Parts express sells Dust caps too. They have paper and Polymer 260-380 ect depending on the diameter. I bought a couple and look fine for woofer replacement but am not sure they would be as rigid as one on a actual current subwoofer.